1. Field of the Invention
The invention is directed to an easily gripped, single use or multiple use packet applicator that contains, protects, dispenses and applies powders, solids, semi-solids, semi-liquids, and liquids. More particularly, the invention provides a method of producing and using a packet applicator, and a packet applicator providing greater convenience and less mess in the application of packet contents. The packet contents, or “payload” adsorbed onto adsorbent pads, are selected from a wide variety of personal care, domestic, office, commercial, and industrial substances. Of particular commercial importance are payloads such as sunscreen, soap, cosmetics, cosmetics removers, powders, and medicaments for application to epidermis and other body surfaces and orifices; detergents, waxes, cleansers, and polishes for application to household, office, and commercial surfaces; and lubricants, paints, solvents, sensors, adhesives, abrasives, and sealants for application to commercial and industrial surfaces.
2. Related Art
One of the unsolved problems of self-contained packet applicators, e.g., sunscreen lotion applicators, glue applicators, cleanser applicators, etc., is the lack of an applicator that (i) provides a package with high packing density and long shelf life, (ii) at the time of application is easy to open and use, (iii) does not coat the user's fingers with payload during application, (iv) adapts the adsorbent pad(s) to the nature of the payload, (v) has high storage density, and (vi) is very inexpensive to manufacture. It also desirable that the packet applicator provide multiple uses (desorptions of payload) and does not leak residual payload between initial opening, subsequent uses, and disposal of the applicator.
The term “payload” means herein the substance to be contained in the packet applicator and applied after the packet is opened. Payload may be a powder, solid, semi-solid, semi-liquid, or liquid (including a volatile or semi-volatile liquid). The term “packet applicator” means a device that contains, protects, dispenses, and applies a payload, and optionally can be resealed to prevent leakage of the payload between initial opening of the packet applicator and dispensing of payload. “Dispensing” means desorption of payload from the adsorbent pad(s) of an opened packet applicator and distribution of the desorbed payload on a target surface. The terms “packet”, “applicator”, and “Kang applicator” hereafter all mean the packet applicator of the invention unless expressly given a different meaning. The term “activated applicator” means an opened packet applicator configured to apply payload. The term “resealed applicator” means a packet applicator that has been previously been opened and thereafter has been resealed for future use or disposal. The term “target surface” means the surface on which a user applies a payload using the applicator (or on which the payload is otherwise deposited, e.g., by evaporation or inhalation). The term “grippability” means the ability of a user to grip one or more surfaces of the applicator in order to open the applicator and to guide the applicator during application of a payload. The term “stray release” means (i) applying payload to any surface other than the intended target surface as well as (ii) payload that leaks from a resealed packet before disposal of the applicator. The term “to package” means to load, contain, and protect a payload in a packet, and, in resealable packets, to also prevent stray release. The term “film” means the planar member in which one or more adsorbent pads (each, an “applicator pad”) is sealed before activation; film is typically paper, woven textile, non-woven textile, plastic, metal, and/or a composite thereof; any of the preceding can be coated with plastic on interior and/or exterior packet surfaces to improve impermeability of the film or grippability of the exterior surface of the packet. An applicator pad can be natural fiber, synthetic fiber, yarn, woven textile, non-woven textile, metal (including steel wool and other “metal wools”), composite, or foam, or a combination of two or more such materials; non-abrasive or gently abrasive materials are used to make applicator pads for personal care embodiments, e.g., facial wipes; medium abrasive pads are used to make applicator pads for some household care embodiments, e,g., glass-top range cleaners; very abrasive materials are used to make applicator pads for some industrial embodiments, e.g., rust removers. “Pore size” and “pad pore size” mean the dimensions of the interstices between the fibers, foam walls, or other structural element of an adsorbent pad in the Kang applicator. A “zip strip” means a mating set of linear, small, plastic lips that can be repeatedly engaged and disengaged, e.g., as commonly used in the resealable margin of sandwich bags. The “top” of an applicator means the film surface of an opened Kang applicator. The “bottom” of an applicator means the surface of an opened Kang applicator with the adsorbent pad(s) exposed.
The prior art of packet applicators, such as that of U.S. Pat. No. 5,470,323 (Smith), U.S. Pat. No. 5,562,642 (Smith), and US App. No. 20040237235 (Visioli) includes applicator pads sandwiched between two rectilinear sheets of film in which three of the four margins are peelably sealed, but cannot be resealed. The Smith applicators have no special provision for holding an opened applicator. The Visioli applicator includes embodiments having structural elements of a gusset or strap on one side of an opened applicator to improve a user's ability to hold and control the applicator, but not a handle on the spine or an opened packet. U.S. Pat. No. 5,957,605 (Cohen) provides special purpose opening tabs and a handle on the spine of the opened applicator, but uses six or more structural elements, including opening tabs and an optional handle stiffener, to make the applicator, compared with two structural elements in the basic embodiment of the Kang applicator.
In its simplest embodiment (i.e., that with the fewest structural elements), Cohen's applicator (U.S. Pat. No. 5,957,605, FIG. 4), comprises an impermeable barrier, an adsorbent pad, two opening tabs, a hole for injection of product, and a hole cover. Although Cohen mentions (U.S. Pat. No. 5,957,605, col. 9, ln. 49-55) alternative, reclosable embodiments that include closure devices such as mating dimples, “a Velcro dot” or a “zip strip” on the outer edge of the applicator, all of which add additional structural elements, no detail about resealable embodiments is disclosed or whether reclosure of the Cohen applicator prevents liquids from leaking from the applicator. The technical problem addressed by Cohen is a multipurpose applicator that is separately manufactured and stockpiled “empty”, then filled with various products in response to product orders. All embodiments of Cohen's applicator have a bulky, complex structure, e.g., a separate outer covering (referred to as a “label” in Cohen), an impermeable barrier (replaced by a label alone in FIG. 4 of Cohen), a product injection aperture, a product dispensing aperture in the impermeable barrier, a thick, full-length adsorbent pad, a handle formed around a reservoir or a stiffener, and opening tabs, and require complex manufacturing compared to the Kang applicator. Cohen introduces significant complexity of applicator structure in exchange for enabling a manufacturer to defer a decision about what product to load in the applicator. Most embodiments of Cohen's applicator have both a label and an impermeable film; a label is typically applied to the exterior of the impermeable film of a generic applicator after the manufacturer decides what payload to insert into the generic applicator. Neither Visioli nor Cohen disclose adapting the characteristics of the adsorbent pad to the nature of the payload. Varying the adsorbent pad characteristics in Cohen's applicator conflicts with Cohen's design limitation of making a generic applicator for which a payload is later selected and injected. The bulky reservoirs and full-length pad of Cohen's applicator greatly reduce the number of applicators that can be stored in a given volume (the number of applicators that can be stored in a given volume is called herein, “storage density”).
The technical problem to be solved is to provide an applicator that (1) packages, dispenses, and applies a variety of payloads, (2) is usable for single or multiple applications, (3) is easy to open and use without stray release, (4) adapts the adsorbent pad(s) to the nature of the payload, (5) has high storage density, and (6) is very inexpensive to manufacture. There is unmet demand for such an applicator in the sectors of pharmaceuticals, personal care, cosmetics, cleaning, painting, adhesives, abrasives, and lubrication.